21 resultados para pacs: expert systems and other ai software and techniques

em BORIS: Bern Open Repository and Information System - Berna - Suiça


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Using a chain of urns, we build a Bayesian nonparametric alarm system to predict catastrophic events, such as epidemics, black outs, etc. Differently from other alarm systems in the literature, our model is constantly updated on the basis of the available information, according to the Bayesian paradigm. The papers contains both theoretical and empirical results. In particular, we test our alarm system on a well-known time series of sunspots.

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Resilience research has been applied to socioeconomic as well as for agroecological studies in the last 20 years. It provides a conceptual and methodological approach for a better understanding of interrelations between the performance of ecological and social systems. In the research area Alto Beni, Bolivia, the production of cocoa (Theobroma cacao L.), is one of the main sources of income. Farmers in the region have formed producers’ associations to enhance organic cocoa cultivation and obtain fair prices since the 1980s. In cooperation with the long-term system comparisons by the Research Institute of Organic Agriculture (FiBL) in Alto Beni, aspects of the field trial are applied for the use in on-farm research: a comparison of soil fertility, biomass and crop diversity is combined with qualitative interviews and participatory observation methods. Fieldwork is carried out together with Bolivian students through the Swiss KFPE-programme Echanges Universitaires. For the system comparisons, four different land-use types were classified according to their ecological complexity during a preliminary study in 2009: successional agroforestry systems, simple agroforestry systems (both organically managed and certified), traditional systems and conventional monocultures. The study focuses on interrelations between different ways of cocoa cultivation, livelihoods and the related socio-cultural rationales behind them. In particular this second aspect is innovative as it allows to broaden the biophysical perspective to a more comprehensive evaluation with socio-ecological aspects thereby increasing the relevance of the agronomic field studies for development policy and practice. Moreover, such a socio-ecological baseline allows to assess the potential of organic agriculture regarding resilience-building face to socio-environmental stress factors. Among others, the results of the pre-study illustrate local farmers’ perceptions of climate change and the consequences for the different crop-systems: all interviewees mentioned rising temperatures and/or an extended dry season as negative impacts more with regard to their own working conditions than to their crops. This was the case in particular for conventional monocultures and in plots where slash-and-burn cultivation was practised whereas for organic agroforestry systems the advantage of working in the shade was stressed indicating that their relevance rises in the context of climate change.

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The aim of this study was to quantify the buffer attributes (value, power, range and optimum) of two model systems for whole human resting saliva, the purified proteins from whole human resting saliva and single proteins. Two model systems, the first containing amyloglucosidase and lysozyme, and the second containing amyloglucosidase and alpha-amylase, were shown to provide, in combination with hydrogencarbonate and di-hydrogenphosphate, almost identical buffer attributes as whole human resting saliva. It was further demonstrated that changes in the protein concentration as small as 0.1% may change the buffer value of a buffer solution up to 15 times. Additionally, it was shown that there was a protein concentration change in the same range (0.16%) between saliva samples collected at the time periods of 13:00 and others collected at 9:00 am and 17:00. The mode of the protein expression changed between these samples corresponded to the change in basic buffer power and the change of the buffer value at pH 6.7. Finally, SDS Page and Ruthenium II tris (bathophenantroline disulfonate) staining unveiled a constant protein expression in all samples except for one 50 kDa protein band. As the change in the expression pattern of that 50 kDa protein band corresponded to the change in basic buffer power and the buffer value at pH 6.7, it was reasonable to conclude that this 50 kDa protein band may contain the protein(s) belonging to the protein buffer system of human saliva.

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Modeling of future water systems at the regional scale is a difficult task due to the complexity of current structures (multiple competing water uses, multiple actors, formal and informal rules) both temporally and spatially. Representing this complexity in the modeling process is a challenge that can be addressed by an interdisciplinary and holistic approach. The assessment of the water system of the Crans-Montana-Sierre area (Switzerland) and its evolution until 2050 were tackled by combining glaciological, hydrogeological, and hydrological measurements and modeling with the evaluation of water use through documentary, statistical and interview-based analyses. Four visions of future regional development were co-produced with a group of stakeholders and were then used as a basis for estimating future water demand. The comparison of the available water resource and the water demand at monthly time scale allowed us to conclude that for the four scenarios socioeconomic factors will impact on the future water systems more than climatic factors. An analysis of the sustainability of the current and future water systems based on four visions of regional development allowed us to identify those scenarios that will be more sustainable and that should be adopted by the decision-makers. The results were then presented to the stakeholders through five key messages. The challenges of communicating the results in such a way with stakeholders are discussed at the end of the article.

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BACKGROUND Pulmonary carcinoids (PCs) are rare tumors. As there is a paucity of randomized studies, this expert consensus document represents an initiative by the European Neuroendocrine Tumor Society to provide guidance on their management. PATIENTS AND METHODS Bibliographical searches were carried out in PubMed for the terms 'pulmonary neuroendocrine tumors', 'bronchial neuroendocrine tumors', 'bronchial carcinoid tumors', 'pulmonary carcinoid', 'pulmonary typical/atypical carcinoid', and 'pulmonary carcinoid and diagnosis/treatment/epidemiology/prognosis'. A systematic review of the relevant literature was carried out, followed by expert review. RESULTS PCs are well-differentiated neuroendocrine tumors and include low- and intermediate-grade malignant tumors, i.e. typical (TC) and atypical carcinoid (AC), respectively. Contrast CT scan is the diagnostic gold standard for PCs, but pathology examination is mandatory for their correct classification. Somatostatin receptor imaging may visualize nearly 80% of the primary tumors and is most sensitive for metastatic disease. Plasma chromogranin A can be increased in PCs. Surgery is the treatment of choice for PCs with the aim of removing the tumor and preserving as much lung tissue as possible. Resection of metastases should be considered whenever possible with curative intent. Somatostatin analogs are the first-line treatment of carcinoid syndrome and may be considered as first-line systemic antiproliferative treatment in unresectable PCs, particularly of low-grade TC and AC. Locoregional or radiotargeted therapies should be considered for metastatic disease. Systemic chemotherapy is used for progressive PCs, although cytotoxic regimens have demonstrated limited effects with etoposide and platinum combination the most commonly used, however, temozolomide has shown most clinical benefit. CONCLUSIONS PCs are complex tumors which require a multidisciplinary approach and long-term follow-up.

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How do institutional settings and their embedded policy principles affect gender-typed enrolment in educational programmes? Based on gender-sensitive theories on career choice, we hypothesised that gender segregation in education is higher with a wider range of offers of vocational programmes. By analysing youth survey and panel data, we tested this assumption for Germany, Norway and Canada, three countries whose educational systems represent a different mix of academic, vocational and universalistic education principles. We found that vocational programmes are considerably more gender-segregated than are academic (e.g. university) programmes. Men, more so than women, can avoid gender-typed programmes by passing on to a university education. This in turn means that as long as their secondary school achievement does not allow for a higher education career, they have a higher likelihood of being allocated to male-typed programmes in the vocational education and training (VET) system. In addition, social background and the age at which students have to choose educational offers impact on the transition to gendered educational programmes. Overall, gender segregation in education is highest in Germany and the lowest in Canada. We interpret the differences between these countries with respect to the constellations of educational principles and policies in the respective countries.

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In this work, electrophoretic preconcentration of protein and peptide samples in microchannels was studied theoretically using the 1D dynamic simulator GENTRANS, and experimentally combined with MS. In all configurations studied, the sample was uniformly distributed throughout the channel before power application, and driving electrodes were used as microchannel ends. In the first part, previously obtained experimental results from carrier-free systems are compared to simulation results, and the effects of atmospheric carbon dioxide and impurities in the sample solution are examined. Simulation provided insight into the dynamics of the transport of all components under the applied electric field and revealed the formation of a pure water zone in the channel center. In the second part, the use of an IEF procedure with simple well defined amphoteric carrier components, i.e. amino acids, for concentration and fractionation of peptides was investigated. By performing simulations a qualitative description of the analyte behavior in this system was obtained. Neurotensin and [Glu1]-Fibrinopeptide B were separated by IEF in microchannels featuring a liquid lid for simple sample handling and placement of the driving electrodes. Component distributions in the channel were detected using MALDI- and nano-ESI-MS and data were in agreement with those obtained by simulation. Dynamic simulations are demonstrated to represent an effective tool to investigate the electrophoretic behavior of all components in the microchannel.

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The study of online reputation systems and their importance for promoting trust and cooperation and, therefore, the smooth functioning of online markets has received considerable attention over the last few years. In the first part of our talk we will try to give a brief overview of the existing theoretical and empirical work in this field, summarize the main findings from this research and identify open questions where results are either controversial or do not yet exist. The second part of our talk will focus on one of these issues that deserve further research, namely the relation between online reputation systems and processes of "cumulative advantage." Cumulative advantage is the mechanism where a favorable relative position of having a good reputation becomes a resource for further relative gains. The process leads to increased status inequality and a heavily skewed distribution of number of feedbacks, i.e. the ties in the reputation network. We present empirical evidence for direct and indirect reputation effects on the micro level of an auction reputation system and discuss the distributional consequences for the market level.

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The presented approach describes a model for a rule-based expert system calculating the temporal variability of the release of wet snow avalanches, using the assumption of avalanche triggering without the loading of new snow. The knowledge base of the model is created by using investigations on the system behaviour of wet snow avalanches in the Italian Ortles Alps, and is represented by a fuzzy logic rule-base. Input parameters of the expert system are numerical and linguistic variables, measurable meteorological and topographical factors and observable characteristics of the snow cover. Output of the inference method is the quantified release disposition for wet snow avalanches. Combining topographical parameters and the spatial interpolation of the calculated release disposition a hazard index map is dynamically generated. Furthermore, the spatial and temporal variability of damage potential on roads exposed to wet snow avalanches can be quantified, expressed by the number of persons at risk. The application of the rule base to the available data in the study area generated plausible results. The study demonstrates the potential for the application of expert systems and fuzzy logic in the field of natural hazard monitoring and risk management.

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This work contributes to the ongoing debate on the productivity paradox by considering CIOs’ perceptions of IT business value. Applying regression analysis to data from an international survey, we study how the adoption of certain types of enterprise software affects the CIOs’ perception of the impact of IT on the firm’s business activities and vice versa. Other potentially important factors such as country, sector and size of the firms are also taken into account. Our results indicate a more significant support for the impact of perceived IT benefits on adoption of enterprise software than vice versa. CIOs based in the US perceive IT benefits more strongly than their German counterparts. Furthermore, certain types of enterprise software seem to be more prevalent in the US.